Papers

A Practical Approach for Designing Operationally Efficient Secondary Distribution Systems

Electric utilities in the US are faced with a unique and often conflicting set of challenges in their current operating environment. They are under increasing pressure to design “smarter” systems and improve operational efficiency, even as the integrity of their physical infrastructure declines, and human resources are more constrained. In order to meet these challenges, today’s distribution designer must be equipped with tools that will help him/her do their job more efficiently. There is a wide range of applications and technologies focused on primary systems, substations and transmission grids, but the design of secondary systems is often overlooked. This paper presents a method and application for the optimal design of secondary systems to meet technical requirements while minimizing total owning costs, including the impact of losses.

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Best Practices for Storm Response on U.S. Distribution Systems

In 2009, the DSTAR consortium commissioned a study of the best practices for utility storm response. The study examined the practices, procedures and experiences of U.S. utilities during major storm occurrences with the goal of understanding and conveying what went right and what went wrong during the build-up, restoration and ramp-down phases. The investigation included detailed utility surveys, interviews with storm bosses, vendors and consultants, and reviews of reports, proceedings, and papers. The result is comprehensive discussion of many important aspects of storm restoration with an emphasis on best practices and lessons-learned from past experiences. This paper summarizes some discussion items and key findings from the study, particularly revealing cases, and recommendations from utility experiences.

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Distribution Transformer Thermal Behavior and Aging in Local Delivery Distribution Systems

This paper characterizes the themal behavior and insulation aging of transformers applied in the local delivery concept of distribution, based on measured data and thermal models.

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DSTAR’s Transformer Cost Analysis Software Enhances Utility Decision Process

Distribution transformers represent a significant cost to electric utilities, both as a capital investment and as an ongoing operating expense. A survey of seven 2003 FERC Form 1 filings shows that distribution transformers can account for approximately 9 to 20% of total distribution capital spending in a year. Productivity tools that help to minimize transformer total owning costs and increase overall asset utilization can make a significant impact on a distribution utility’s bottom line. The Distribution Systems Testing, Application, and Research (DSTAR) utility consortium commissioned the development of the Transformer Owning Cost Software (TOCS) tool for analyzing and comparing the total owning cost of distribution transformers. This white paper describes the concepts and applications of the tool.

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The Breakdown and Mitigation of Technical Losses on Distribution Power Systems

There has been an increasing focus on energy efficiency and demand reduction among utility companies and regulatory agencies in the United States. Technical losses within distribution systems are under increasing scrutiny. One of the key issues is to understand where losses occur along a “typical” feeder and what aspects of feeder engineering and construction contribute to or mitigate losses. In a recent project1, the DSTAR utility research consortium looks for answers to both questions. This paper summarizes approaches and findings from the project.

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